Production of titanium tetraiodide



Patented Aug. 22, 1950 UNITED STATES PATENT OFFICE PRODUCTION OF TITANIUM TETRAIODIDE No Drawing. Application April 12, 1948, Serial No. 20,595

6 Claims.

This invention relates to the production of metallic titanium and has for an object the provision of an improved method or process for producing high-purity metallic titanium. More particularly, the invention contemplates the provision of an improved method or process for producing high-purity metallic titanium by dissociation of titanium tetraiodide.

According to some heretofore customary procedures, metallic titanium of high purity is produced by contacting titanium tetraiodide with a heated surface maintained at a temperature in the range 1100 C. to 1700" C. Contact of the titanium tetraiodide with the heated surface results in dissociation of the iodine and titanium of the titanium tetraiodide with the deposition of the titanium on the heated surface and with the production of a gaseous product containing the iodine in vapor form. Titanium or tungsten or some other suitable metal is employed in forming the heated surface.

According to some heretofore customary processes, the titanium tetraiodide employed is formed by contacting iodine in vapor form with crude metallic titanium.

According to the process of my invention, titanium tetraiodide is produced by contacting elemental iodine in vapor form with titanium carbide. The production of titanium tetraiodide by reaction of iodine in vapor form with titanium carbide is described and claimed in my co-pending applications, Serial Nos. 20,593, and 20,598, both filed April 12, 1948.

In the production of titanium tetraiodide by reaction of iodine with titanium carbide, as de' scribed in my aforementioned co-pending applications, the elemental iodine in vapor form is contacted with the titanium carbide at a temperature near 1100 C.

The present invention is based on my discovery that the reaction between elemental iodine in vapor form and titanium carbide is accelerated and may be carried out at a lower temperature if carried out in the presence of a small amount of titanium tetrachloride. In the presence of titanium tetrachloride, the reaction proceeds at least as rapidly at 1600 C. as it does at 1100" C. in the absence of titanium tetrachloride.

The iodine and titanium tetrachloride may be employed in any desired proportions, but a mixture of iodine and titanium tetrachloride in which the titanium tetrachloride is present in amount by weight equal to about one to five percent (l.% to 5%) of the weight of the iodine will produce satisfactory results.

The titanium tetrachloride functions somewhat in the manner of a catalyst in accordance with reactions illustrated by the following equations:

The gaseous product resulting from treatment of the titanium carbide with iodine in the presence of titanium tetrachloride contains titanium tetraiodide and titanium tetrachloride. Excess iodine may be present, also, in the gaseous product resulting from the treatment of titanium carbide with iodine. The boiling point of titanium tetrachloride is 136x? C. The boiling point of titanium tetraiodide is 379 C. Quantitative separation of the two compounds can be effected by means of a suitable fractionating treatment as, for example, by fractional condensation of the gaseous products or by complete condensation of the gaseous product followed by fractional distillation. The separated titanium tetrachloride may be returned to the process for re-use.

In the fractionation treatment, the iodine and the titanium tetrachloride present in the gaseous product may be separated together and returned together to the process for re-use in treating titanium carbide.

I claim:

1. The method of preparing titanium tetraiodide which comprises heating titanium carbide with iodine in vapor form in the presence of titanium tetrachloride to produce a gaseous product comprising titanium tetraiodide and titanium tetrachloride.

2. The method of preparing titanium tetraiodide which comprises subjecting titanium carbide to the action of iodine in vapor form at a temperature of about 1000 C. in the presence of titanium tetrachloride.

3. The method of preparing titanium tetraiodide which comprises heating titanium carbide 3 with iodine in vapor form in the presence of titanium tetrachloride to produce a gaseous product comprising titanium tetraiodide and titanium tetrachloride, and i'ractionating the gaseous product to obtain separate titanium tetraiodide and titanium tetrachloride products.

4. The method of preparing titanium tetraiodide which comprises subjecting titanium carbide to the action of iodine in vapor form at a temperature of about 1000 C. in the presence of titanium tetrachloride to produce a gaseous product comprising titanium tetraiodide and titanium tetrachloride, and fractionating the gaseous product to obtain separate titanium tetraiodide and titanium tetrachloride products.

5. The method of preparing titanium tetraiodide which comprises heating titanium carbide with iodine in vapor form in the presence of titanium tetrachloride to produce a gaseous product comprising titanium tetraiodide and titanium tetrachloride, fractionating the gaseous product to obtain separate titanium tetraiodide and titanium tetrachloride products, and returning the titanium tetrachloride to the process for re-use.

6. The method of preparing titanium tetraiodide which comprises subjecting titanium carbide to the action of iodine in vapor form at a temperature of about 1000 C. in the presence of titanium tetrachloride to produce a gaseous product comprising titanium tetraiodide and titanium tetrachloride, fractionating the gaseous product to obtain separate titanium tetraiodide and titanium tetrachloride products, and returning the titanium tetrachloride to the process for re-use.

ALFRED C. LOONAM.

No references cited. 

3. THE METHOD OF PREPARING ITANIUM TETRAIODIDE WHICH COMPRISES HEATING TITANIUM CARBIDE WITH IODINE IN VAPOR FORM IN THE PRESENCE OF TITANIUM TETRACHLORIDE TO PRODUCE A GASEOUS PRODUCT COMPRISING TITANIUM TETRAIODIDE AND TITANIUM TETRACHLORIDE, AND FRACTIONATING THE GASEOUS PRODUCT TO OBAIN SEPARATE TITANIUM TETRAIODIDE AND TITANIUM TETRACHLORIDE PRODUCTS. 